A test system for electronic device testing can include a pin driver circuit that provides a voltage test pulse or current test pulse to a device under test (DUT). In response, the test system can be configured to measure a response from a DUT, such as to determine whether the DUT meets one or more specified operating criteria.
In an example, test systems can include dynamic controls for delivering timing signals, including controls for synchronizing or deskewing multiple signals to be provided to, or received from, a DUT. The timing signals can be used to perform tests on a variety of integrated circuit devices. In each test, one or more timing signals can be applied to respective pins of a DUT, and corresponding response signals can be analyzed. The timing signals may travel to each DUT pin by a different path, and response signals from the DUT can similarly travel different paths to response analysis circuitry. Such differences in propagation paths, or other influences on signal timing or propagation, can influence test results. Various techniques can be used to correct, or to more precisely control, the timing of test signals that are desired to arrive at a DUT at precise times or in synchronization.
Timing errors are generally referred to herein as “skew”. In an early approach to deskewing signals, a number of manually adjustable potentiometers were associated with each pin for aligning in time each pin's input signal. The potentiometers could be adjusted whenever the system required recalibration.
In another approach, a deskewing system can include a sequence of stages for delaying the signal. A more coarse stage can delay a signal by multiples of a predetermined delay interval and a finer stage can provide for finer adjustment of the delay interval.